Vehicle brake assembly

ABSTRACT

A brake assembly adapted to be mounted on a motor vehicle axle member and constructed to permit removal of the assembly brake shoes for relining without removal of the brake drum or other structure located outboard of the assembly. The assembly includes a spider abutting the outboard surface of and secured to a radial flange formed on the axle. The spider carries brake shoes located inboard of the spider-axle flange interface that are held in place by brake shoe return springs attached to the shoes and the inboard face of the spider at a point easily accessible from inboard of the assembly. Lateral brake shoe movement along the axle axis is prevented by brake shoe retaining members normally located outboard and inboard of the brake shoes. The inboard of these retaining members are removable to permit the brake shoes to be removed from the assembly by inboard movement thereof.

llnite States Patent Nehr 5] May 36, 1972 [54] VECLE BRAKE ASSIE 1 1: LY

Primary Examiner-Duane A. Reger [72] y Charles Nehr Bloomfield Mlch'Attorney-John R. Bronaugh, E. Dennis O'Connor and Floyd [73] Assignee:North American Rockwell Corporation, 3 Levison Pittsburgh, Pa. [22]Filed: July 13, 1970 [57] ABSTRACT A brake assembly adapted to bemounted on a motor vehicle [21] Appl. No.: 54,173 axle member andconstructed to permit removal of the assembly brake shoes for reliningwithout removal of the brake 52] Us. CL "188/206 R, 188/216, 188/335,drum or other structure located outboard of the assembly. The 188/340assembly includes a spider abutting the outboard surface of 51 Int. Cl..F16d 65/08 and Secured radial flange fmmed The spider 58 Field ofSearch ..1ss/2 R, 18 R, 206 A, 206 R, carries brake mated inbwd spidemleflange 188/216, 250 C 326, 335, 340 343 interface that are held in placeby brake shoe return springs attached to the shoes and the inboard faceof the spider at a point easily accessible from inboard of the assembly.Lateral [56] References Cited brake shoe movement along the axle axis isprevented by NITED ES PATENTS brake shoe retaining members normallylocated outboard and inboard of the brake shoes. The inboard of theseretaining 2,082,244 6/1937 Dick ..188/34O members are removable topermit the brake shoes to be 1,551 1 1/1 947 Goepfrlchfl 1 88/206 Xremoved from the assembly by inboard movement thereof. 3,339,677 9/1967Behnke ....188/206 A X 3,378,l 13 l-lanley et a1. 1 88/206 A 9 Claims, 3Drawing Figures Patented May 30, 1972 3,666,061

2 Sheets-Sheet 1 INVENTOR. (7471 5 14 44 Patented May 30, 1972 3,666,061

2 Sheets-Sheet 2 INVENTOR.

VEHICLE BRAKE ASSELY BACKGROUND OF THE INVENTION In order to remove thebrake shoes for relining in certain conventional motor vehicle brakeassemblies, it is necessary to disassemble'large portions of the vehicleaxles mounting such brake assemblies in order to gain access to andpermit removal of the brake shoes. An example of such an assembly is onemounted on a vehicle drive axle of the planetary type. This type ofdrive axle has a planetary gear set, as well as a conventional brakedrum, wheel and rim, mounted outboard of each of the brake assembliescarried by the axle. In many heavy equipment applications, these gearsets are extremely large in size and weight and can be removed from theaxle only by use of special equipment such as a hoist or crane. Largelabor efforts also must be expended to accomplish removal of such gearsets.

The relining of brake shoes is part of the regular maintenance programthat must be accomplished periodically on a vehicle brake assembly inorder to insure satisfactory brake performance and vehicle operation. Itthus readily can be understood that if brake shoe relining must bepreceded by the removal of planetary gear sets as well as brake drums,wheels and rims the accomplishment of this ordinary maintenanceoperation will result in lengthy vehicle down time due to the necessaryuse of special equipment and the performance of time consuming manualtasks. Also, substantial efforts and time must be expended even if noplanetary gear set is involved, as all structure carried by the axleoutboard of conventional brake assemblies must be removed from the axleand reassembled attendant a brake relining job.

An object of this invention is to provide a vehicle brake assemblydesigned and constructed so that the brake shoes can be removed forinspection and/or relining without the need to remove any of the vehiclestructure carried outboard of the brake assembly by the axle mountingthis brake assembly. This simplification of relining procedure allowsgreat economic savings by reducing vehicle down time.

In particular,.the brake assembly of this invention is such that thebrake shoe return springs securing the brake shoes to the spider areaccessible from inboard the brake assembly and easily may be detachedmanually from the spider. In addition, the inboard brake shoe retainingmember normally located inboard of the brake assembly easily may beremoved so that the brake shoe may be taken from the brake assembly by aworkman working from inboard the brake assembly.

DESCRIPTION OF THE DRAWINGS FIG. I is a side view, partly in section andpartly in elevation, illustrating a vehicle brake assembly according tothis invention and illustrating in phantom certain attendant structure;

FIG. 2 is a view taken along the line of sight identified by the arrow 2in FIG. 1, with portions of the structure shown in FIG. I removed forpurposes of clarity; and

FIG. 3 is a partial section view taken along the line 3--3 of FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION Referring now in detail to thedrawings and in particular to FIGS. 1 and 2 thereof, the numeral denotesgenerally a vehicle brake assembly constructed in accordance with thisinvention. This assembly includes a support member or spider 12 havingan inboard face 14, a portion of which abuts the outboard face of aradially extending flange l6 projecting from a vehicle axle member 18.As is conventional, member 18 extends through a central aperture formedin spider l2.

Integrally formed as part of spider 12 are upper and lower brakeactuating mechanism housings 22 and 24. Fluid motors 26 and 28 aresecured to housings 22 and 24 respectively such that the motor outputmembers 30 and 32 extend into the housings 22 and 24. The brakeactuating mechanisms of assembly 10, including the fluid motors 26 and28 and the structure contained within the housings 22 and 24, do notconstitute part of the present invention and may be the brake actuatingmechanisms described in US. Pat. No. 3,322,241, issued May 30, 1967, toF. T. Cox et al., and assigned to the assignee of this invention. It issufficient for purposes of this description to note that upon actuationof fluid motors 26 and 28, motor output members 30 and 32 move withinhousings 22 and 24 and a following movement of brake shoe actuatingmembers 34, 35 and 36, 37 outwardly away from housings 22 and 24 occurs.

Positioned about a portion of the outer periphery of spider 12 is abrake shoe 38. Opposite ends of brake shoe 38 are contacted by actuatingmembers 34 and 36 so that movement of these actuating members away fromthe housings 22 and 24 will cause a radially outward movement of brakeshoe 38 and the lining 40, secured to the outer extremity of the brakeshoe, will contact brake drum 42 for braking action.

A second brake shoe, identical to brake shoe 38, is positioneddiametrically across spider 12 from brake shoe 38 and is in contact withactuating members 34 and 35. This second brake shoe has been omittedfrom FIG. 2 of. the drawings for purposes of clarity. It readily may beunderstood that the construction and operation of this second brake shoeare identical to that detailed herein relative to brake shoe 38.

Lateral movement of brake shoe 38, that is movement of the brake shoe ininboard and outboard directions along the axis of axle member 18,effectively is prohibited by a plurality of retainers. A pair ofoutboard retainers 44 and 45 are integrally formed with and project fromspider 12. (The outboard retainers 46 and 47 utilized to position thesecond brake shoe that is not illustrated clearly may be seen in FIG.2.) Inboard movement of brake shoe 38 is prevented by the presence ofinboard retainers 48 and 49 secured to spider 12 by fasteners 48a and49a respectively.

The inboard and outboard retainers locating brake shoe 38 laterallycooperate to define outwardly open ended channel 50 between retainers 44and 48, and channel 52 between retainers 45 and 49. Upon the actuationof fluid motors 26 and 28, radially directed outward movement of brakeshoe 38 occurs within channels 50 and 52.

Referring now in particular to FIGS. 1 and 3 of the drawings, it may beseen that the mid portion 54 of brake shoe 38 is bifurcated and definesan aperture 56 extending therethrough in a radial direction. Thisaperture extends through the inner face 57 of brake shoe 38 andcommunicates with a recess 58 formed in the outer face of the brakeshoe. A brake lining 39 closes the outer extremity of recess 58. A pairof spring attachment members 60 and 61 are located within recess 58.These attachment members are placed in the recess 58 prior to the brakeshoe lining 39 being secured to the outer face of brake shoe 38.

A pair of tension coil springs 62 and 64 are located within aperture 56and extend generally radially. The outer ends of springs 62 and 64 aresecured to spring attachment members 60 and 61 respectively. Each of theinner ends of these springs is secured to one of pins 66 and 68 thatextend from the inboard face 14 of spider 12. As readily may be seenfrom FIG. 3, pin 66 has a threaded end that is received in a threadedbore 70 formed in spider 12. Pin 68 is secured to the spider in asimilar manner.

The interconnection between spider 12 and brake shoe 38 by springs 62and 64 provides an inwardly directed force on the brake shoe thatreturns the brake shoe to the normal position, remote from drum 42, uponthe deactivation of the fluid motors 26 and 28.

The design and construction of the vehicle brake assembly describedheretofore permits removal of the brake shoe for inspection and/orreplacement of the brake shoe linings without the necessity of removingbrake drum 42 and other structure positioned outboard of the brakeassembly on the axle member 18. The brake shoes may be removed by aworkman working from a position inboard of the brake assembly 10 as isdescribed below.

As may be seen most clearly from FIG. 1, brake shoe 38 has negativeoffset. This term describes the orientation of the brake shoe whereinthe center line of the brake shoe is located inboard of the interfacebetween spider 12 and flange 16. The brake shoe center line extendsthrough the centers of both of springs 62 and 64 as viewed in FIG. 1.

This arrangement allows springs 62 and 64 effectively to be secured tothe inboard face of spider l2 and allows the points of attachment atpins 66 and 68 readily to be accessible from inboard brake assembly asmay be seen from FIG. 2. The procedure for removing brake shoe 38 thusfirst involves detaching springs 62 and 64 from pins 66 and 68. A simpletool such as a screwdriver may be utilized for this operation. It may bedesirable to adjust the inactivated position of one or both of actuatingmembers 34 and 36 prior to the detachment of springs 62 and 64 in orderto lessen the tension forces on these springs and facilitate theirremoval from pins 66 and 68.

Inboard retaining members 48 and 49 then are removed by removal offasteners 48a and 49a. Brake shoe 38 then is free to be manipulatedmanually and moved in an inboard direction along the axis of axle member18 for removal from brake assembly 10. The second brake shoe notillustrated may be removed in a manner similar to the removal of brakeshoe 38.

It thus may be seen that this invention provides a vehicle brakeassembly having brake shoes that may be removed from the assembly forinspection and/or repair without the necessity of removing from thevehicle axle mounting the assembly structure located outboard of theassembly.

lclaim:

1. A vehicle brake assembly adapted to be mounted on a vehicle axlemember, said axle member having a radial projection extending therefrom,said brake assembly including: a brake shoe supporting membersurrounding said axle outboard of said projection and having an inboardsurface at least a portion of which abuts the outboard face of saidprojection, at least one brake shoe carried by said supporting memberand capable of radially directed movement relative thereto, and brakeshoe actuating means carried by said supporting member, operativelybearing on said brake shoe and capable of exerting a force urging saidbrake shoe radially outwardly towards and into contact with asurrounding brake drum, and resilient means having one portionthereofoperatively secured to said brake shoe, another portion thereofoperatively secured to said inboard surface of said supporting memberand positioned inboard of said supporting member, said resilient meansexerting a force acting on said brake shoe in a direction opposite thedirection of the force exerted by said actuating means.

2. A vehicle brake assembly according to claim 1, further including apair of axially spaced apart retaining means projecting radially fromsaid supporting member and defining therebetween a channel in which saidbrake shoe is received, said retaining means normally being spaced apartaxially a distance such that said retaining means prevent axial movementof said brake shoe, the inboard of said retaining means being removablefrom said supporting member to permit inboard directed axial movement ofsaid brake shoe.

3. A vehicle brake assembly according to claim 1, wherein said brakeshoe is formed with a generally radially extending passageway formedtherein and being open through the surface of said brake shoe proximatethe axis of said axle member, said resilient means being elongated andhaving one end thereof operatively secured to said brake shoe withinsaid passageway and extending radially inwardly out of said passagewayto a point whereat the other end of said resilient means is operativelyconnected to the inboard surface of said supporting member.

4. A vehicle brake assembly according to claim 3, wherein said resilientmeans comprises a tension coil spring.

5. A vehicle brake assembly adapted for mounting on an elongatedgenerally horizontal vehicle axle member, said axle member havingD aradially projecting flange extending therefrom, said rake assemblyincluding: a spider having a central aperture extending therethrough andreceiving said axle member such that a portion of the inboard surface ofsaid spider abuts the outboard surface of said flange, said spider beingsecured to said flange by fastening means, at least one brake shoecarried by said spider radially outwardly thereof and capable of radialmovement relative thereto, said brake shoe being located inboard of theinterface between said spider and said flange, tension spring meansoperatively interconnecting said brake shoe and said spider and beinglocated inboard of said spider, said spring means exerting a force urging said brake shoe toward said spider, and brake shoe actuating meanscarried by said supporting member and contacting said brake shoe, saidactuating means having an inoperative condition wherein said actuatingmeans are positioned such that said spring is placed under a firsttension and an operative condition wherein said actuating means exert aforce overcoming the force ofsaid spring and urging said brake shoeoutwardly towards and into contact with a surrounding brake drum.

6. A vehicle brake assembly according to claim 5, further including apair of axially spaced apart retaining means projecting radially fromthe outer periphery of said spider and defining therebetween anoutwardly open ended channel in which said brake shoe is positioned,said retaining means normally being spaced apart axially a distance suchthat said retaining means prevent axial movement of said brake shoe, theinboard of said retaining means being removable from said spider topermit axially inboard directed movement of said brake shoe.

7. A vehicle brake assembly according to claim 5, wherein said brakeshoe is formed with a generally radially extending passageway formedtherein and being open through the surface of said brakeshoe proximatethe axis of said axle member, said resilient means being elongated andhaving one end thereof operatively secured to said brake shoe withinsaid passageway and extending radially inwardly out of said passagewayto a point whereat the other end of said resilient means is operativelyconnected to the inboard surface of said spider.

8. A vehicle brake assembly according to claim 5, wherein said brakeshoe comprises a main body and a brake lining secured to the outersurface ofsaid main body, said main body having a recess formed thereinproximate said lining, a spring attachment member positioned in saidrecess, said main body having a passageway extending from said recessthrough the inward surface thereof, said spring means comprising anelongated coil spring having a portion thereof extending into saidpassageway and terminating in one end that is secured to said attachmentmember, the other end of said spring being operatively secured to theinboard surface of said spider.

9. A vehicle brake assembly according to claim 5, wherein said springmeans comprises an elongated coil spring, the inboard surface of saidspider having a pin extending therefrom, one end of said spring beingattached to said pin at a point readily accessible from inboard ofsaidbrake assembly.

1. A vehicle brake assembly adapted to be mounted on a vehicle axlemember, said axle member having a radial projection extending therefrom,said brake assembly including: a brake shoe supporting membersurrounding said axle outboard of said projection and having an inboardsurface at least a portion of which abuts the outboard face of saidprojection, at least one brake shoe carried by said supporting memberand capable of radially directed movement relative thereto, and brakeshoe actuating means carried by said supporting member, operativelybearing on said brake shoe and capable of exerting a force urging saidbrake shoe radially outwardly towards and into contact with asurrounding brake drum, and resilient means having one portion thereofoperativeLy secured to said brake shoe, another portion thereofoperatively secured to said inboard surface of said supporting memberand positioned inboard of said supporting member, said resilient meansexerting a force acting on said brake shoe in a direction opposite thedirection of the force exerted by said actuating means.
 2. A vehiclebrake assembly according to claim 1, further including a pair of axiallyspaced apart retaining means projecting radially from said supportingmember and defining therebetween a channel in which said brake shoe isreceived, said retaining means normally being spaced apart axially adistance such that said retaining means prevent axial movement of saidbrake shoe, the inboard of said retaining means being removable fromsaid supporting member to permit inboard directed axial movement of saidbrake shoe.
 3. A vehicle brake assembly according to claim 1, whereinsaid brake shoe is formed with a generally radially extending passagewayformed therein and being open through the surface of said brake shoeproximate the axis of said axle member, said resilient means beingelongated and having one end thereof operatively secured to said brakeshoe within said passageway and extending radially inwardly out of saidpassageway to a point whereat the other end of said resilient means isoperatively connected to the inboard surface of said supporting member.4. A vehicle brake assembly according to claim 3, wherein said resilientmeans comprises a tension coil spring.
 5. A vehicle brake assemblyadapted for mounting on an elongated generally horizontal vehicle axlemember, said axle member having a radially projecting flange extendingtherefrom, said brake assembly including: a spider having a centralaperture extending therethrough and receiving said axle member such thata portion of the inboard surface of said spider abuts the outboardsurface of said flange, said spider being secured to said flange byfastening means, at least one brake shoe carried by said spider radiallyoutwardly thereof and capable of radial movement relative thereto, saidbrake shoe being located inboard of the interface between said spiderand said flange, tension spring means operatively interconnecting saidbrake shoe and said spider and being located inboard of said spider,said spring means exerting a force urging said brake shoe toward saidspider, and brake shoe actuating means carried by said supporting memberand contacting said brake shoe, said actuating means having aninoperative condition wherein said actuating means are positioned suchthat said spring is placed under a first tension and an operativecondition wherein said actuating means exert a force overcoming theforce of said spring and urging said brake shoe outwardly towards andinto contact with a surrounding brake drum.
 6. A vehicle brake assemblyaccording to claim 5, further including a pair of axially spaced apartretaining means projecting radially from the outer periphery of saidspider and defining therebetween an outwardly open ended channel inwhich said brake shoe is positioned, said retaining means normally beingspaced apart axially a distance such that said retaining means preventaxial movement of said brake shoe, the inboard of said retaining meansbeing removable from said spider to permit axially inboard directedmovement of said brake shoe.
 7. A vehicle brake assembly according toclaim 5, wherein said brake shoe is formed with a generally radiallyextending passageway formed therein and being open through the surfaceof said brakeshoe proximate the axis of said axle member, said resilientmeans being elongated and having one end thereof operatively secured tosaid brake shoe within said passageway and extending radially inwardlyout of said passageway to a point whereat the other end of saidresilient means is operatively connected to the inboard surface of saidspider.
 8. A vehicle brake assembly according to claim 5, wherein saidbrake shoe comprises a main body aNd a brake lining secured to the outersurface of said main body, said main body having a recess formed thereinproximate said lining, a spring attachment member positioned in saidrecess, said main body having a passageway extending from said recessthrough the inward surface thereof, said spring means comprising anelongated coil spring having a portion thereof extending into saidpassageway and terminating in one end that is secured to said attachmentmember, the other end of said spring being operatively secured to theinboard surface of said spider.
 9. A vehicle brake assembly according toclaim 5, wherein said spring means comprises an elongated coil spring,the inboard surface of said spider having a pin extending therefrom, oneend of said spring being attached to said pin at a point readilyaccessible from inboard of said brake assembly.